The human body is unable to live in space for a long time, so when astronauts have to stay in the International Space Station (ISS) for months, they can expect changes in their bodies, such as the case of American astronaut Scott Kelly, who spent a year aboard the ISS for a full year back in 2015.
Scott stayed longer than what is normal in space that the experience caused some changes when he came back to Earth, including a change in his gut microbiome, and even a slight change in his DNA compared to his twin, former astronaut Mark Kelly-- all of which are documented in several research papers, according to the press release by National Aeronautics and Space Administration (NASA).
Furthermore, the astronaut experienced sore feet for three months after coming back to Earth.
While humans changed and adapted to the challenging environment up in space, a species of bacteria originally found in a can of meat basically had no problems living in space.
What's surprising is that the bacterium, known as Deinococcus radiodurans, lived outside of the ISS, where it has no protection against UV radiation, weightlessness, and the variety of threats in space.To read more, click here.